The number of integral roots of the equation x^4+under root (x^4+20)=22 is?

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Oddman answered
Substituting y = x^4, we get
  y + √(y+20) = 22
  √(y+20) = 22 - y
  y + 20 = (22 - y)^2 = 484 - 44y + y^2
  y^2 - 45y + 464 = 0
  (y - 29)(y - 16) = 0
  x^4 = 16 has two integral roots:
  X = 2, x = -2

It also has 6 other roots, of which 4 are imaginary, assuming the "under root" can be taken as positive or negative.

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